Halitosis, the medical term for bad breath, represents a persistent, unpleasant odor from the mouth. This condition, often more than just occasional foul smells, can be influenced by factors like dietary choices, oral hygiene, or underlying medical issues1.

Halitosis Symptoms: What Does Halitosis Smell Like?

What does halitosis smell like? The quick answer is: It varies, with the smell largely influenced by the root cause. Some describe halitosis as having a rotten egg or sulfurous aroma, which may be linked to digestive issues or sulfuric proteins in the mouth2. A sweet or fruity-scented bad breath could be indicative of conditions like diabetes2, which requires medical attention. A breath that smells mothball-like might be due to bacteria and conditions causing excess mucus3, while a bad breath that smells like poop may suggest bowl construction2. Musty odors can hint at liver diseases2, and a fishy smell might point to metabolic diseases2. It is important to talk to your doctor about underlying medical conditions that can influence bad breath.

  1. Is Halitosis Contagious?

    Halitosis itself isn't contagious4. However, while you can't "catch" bad breath from someone, it's possible to contract the harmful bacteria that lead to it through intimate actions such as kissing, or sharing personal items like utensils or toothbrushes5. Therefore, while you can't catch halitosis directly, it's always wise to maintain good oral hygiene and be cautious with personal exchanges to minimize the risk of harmful bacteria transmission.

Halitosis (Bad Breath) Causes

  1. Bad Breath Due to Other Oral Issues

    The most common cause of halitosis or bad breath is poor oral hygiene6. Without proper oral hygiene – like brushing, flossing, and rinsing with mouthwash – food particles remain in the mouth, promoting bacterial growth between teeth, around the gums, and on the tongue7.

    Bacteria in the mouth produce waste byproducts which are the primary cause of the foul odor of bad breath. Prolonged unchecked bacterial growth can worsen oral health issues, intensifying halitosis. Major halitosis-causing oral issues include6,8:

    • Tooth Decay: Tooth Decay is primarily due to the demineralization of teeth (losing mineral from teeth), leading to tooth cavities, which can cause bad breath.
    • Gum Disease (Periodontitis and Gingivitis): Infected gums can bleed and produce pus, contributing to bad breath.
    • Tooth Abscesses: Pockets of pus caused by bacterial infections can give off a noticeable odor.
    • Coated Tongue: A layer of bacteria and dead cells on the tongue can lead to a persistent bad taste and breath odor.
    • Poorly Fitted Dental Appliances: Braces, dentures, or other appliances can trap food and bacteria, worsening halitosis.
    • Oral Infections: Infections resulting from tooth extractions or surgeries can cause an increase in bad breath.
  2. Avoid Food that Causes Bad Breath

    Diet plays an important role in determining the quality of one's breath. The smells of some foods, once ingested, can linger, contributing to an unpleasant breath. Additionally, foods that foster bacterial growth in the mouth can also lead to halitosis as the bacteria produce foul-smelling byproducts7. Common foods contributing to halitosis include:

    • Garlic and Onions9: Their strong odor can linger in your mouth.
    • Coffee9: When roasted, coffee forms sulfur-containing aroma compounds which, combined with its natural acid content, can lead to bad breath.
    • Alcoholic Beverages9: Consumed alcohol is converted into acetic acid during digestion, resulting in a strong, vinegar-like odor.
    • Dairy Products9: Milk and cheese can leave residues that bacteria feed on, producing sulfur compounds.
    • High Protein Foods10: Our body releases ammonia during the protein breakdown process, resulting in a pronounced smell.
    • Tuna and Other Fish: They have a naturally strong odor that can linger in the mouth, compounded by the sour smell seafood develops as it oxidizes.
    • Refined and Processed Sugars11: Bacteria thrive on sugar, leading to increased bacterial growth.
  3. Medical Conditions and Halitosis

    The health of your mouth says a lot about your overall health. Halitosis, while often resulting from oral issues, can also be a sign of underlying systemic conditions. Some health issues can produce specific chemicals or bacteria that manifest as bad breath. Additionally, certain conditions may cause postnasal drip, dry mouth, or other symptoms that can foster bacterial growth in the mouth, leading to halitosis. Health conditions linked to halitosis include6,8:

    • Sinus Infections: Sinus inflammation or infections may result in postnasal drip, creating a substrate for bacterial proliferation.
    • Tonsil Stones: Calcified lumps at the back of the throat can produce a foul odor.
    • Gastroesophageal Reflux Disease: Acid reflux can bring up stomach contents, contributing to bad breath.
    • Diabetes: Patients with diabetes are more susceptible to infections and face challenges with wound healing. Among this group, periodontal disease is the most common oral disease which can be a significant contributor to halitosis.
    • Liver or Kidney Disease: In people with liver or kidney disease, toxins might not be effectively cleared out from the body which can cause breath to smell.
    • Respiratory Tract Infections: Conditions like bronchitis or pneumonia can produce bad breath.
    • Chronic Dry Mouth (Xerostomia): Reduced saliva production, often due to medication side effects or other conditions, can foster bacterial growth.

Halitosis (Bad Breath) Treatment

  1. How to Get Rid of Bad Breath at Home

    Home Remedy #1: Brushing

    Regular brushing of teeth, especially after meals, helps to remove food particles and prevent bacterial growth on the teeth and gums.

    Home Remedy #2: Flossing

    Flossing accesses the gaps between teeth, areas a toothbrush often misses. Proper flossing removes trapped food particles and decreases bacterial accumulation, thus helping prevent bad breath.

    Home Remedy #3: Using Mouthwash

    While brushing and flossing are vital to proper oral care, they only reach 25% of the mouth. Adding a 30-second rinse with a mouthwash for bad breath like LISTERINE® offers a virtually 100% whole mouth clean. LISTERINE® is clinically proven to kill 99.9% of germs causing bad breath, plaque and gingivitis.

  2. When to See a Doctor or Dentist About Bad Breath

    You should always check in with your doctor if you have persistent bad breath. Persistent, chronic bad breath or a sudden change in breath odor can sometimes indicate an underlying medical condition or dental issue. Consulting your primary care doctor is essential to identify other potential causes of halitosis1.

Illustration of a smile

How to Get Rid of Halitosis at Home

While brushing your teeth is necessary, one of the best halitosis home remedies is to focus on cleaning your tongue, because it’s where a large amount of the bacteria live. Clean it with a tongue scraper then rise with mouthwash, like LISTERINE®, to help kill germs that can lead to bad breath.

Remember that brushing alone reaches only 25% of your mouth. Rinsing with mouthwash allows you to clean virtually your entire mouth and helps freshen your breath. A twice-daily routine of brushing, flossing and rinsing with an antiseptic mouthwash like LISTERINE® Mouthwash can help prevent and treat halitosis.

Professional Halitosis Treatment

If you don’t notice an improvement with halitosis home remedies, you should visit your dentist. Don’t be afraid or embarrassed to share your condition with a licensed professional. They’ll likely be able to diagnose it and help you find the best treatment option for you.

1 - Cleveland Clinic. Halitosis (Bad Breath): What It Is, Causes & Treatment. Retrieved from: https://my.clevelandclinic.org/health/symptoms/17771-bad-breath-halitosis
2 - Healthline. Types of Bad Breath Smells: Causes, Treatment, Prevention. Retrieved from: https://www.healthline.com/health/types-of-bad-breath-smells
3 - Healthline. Breath Smells Like Mothballs: Causes and Solutions. Retrieved from: https://www.healthline.com/health/breath-smells-like-mothballs
4 - Nwhator S, Isiekwe G, Soroye M, Agbaje M. Bad-breath: Perceptions and misconceptions of Nigerian adults. Niger J Clin Pract. 2015;18(5):670. doi:10.4103/1119-3077.158974
5 - MyDentalAdvocate. Is Gingivitis & Gum Disease Contagious? Retrieved from: https://mydentaladvocate.com/is-gingivitis-gum-disease-contagious-what-t...
6 - Aylikci B, Çolak H. Halitosis: From diagnosis to management. J Nat Sc Biol Med. 2013;4(1):14. doi:10.4103/0976-9668.107255
7 - American Dental Association. Bad breath. J Am Dent Assoc. 2012;143(9):1053. doi:10.14219/jada.archive.2012.0337
8 - Madhushankari G, Yamunadevi A, Selvamani M, Mohan Kumar K, Basandi P. Halitosis - An overview: Part-I - Classification, etiology, and pathophysiology of halitosis. J Pharm Bioall Sci. 2015;7(6):339. doi:10.4103/0975-7406.163441
9 - WebMD. Bad Breath: Good and Bad Foods. Retrieved from: https://www.webmd.com/oral-health/features/bad-breath-good-and-bad-foods
10 - Lee PPC, Mak WY, Newsome P. The aetiology and treatment of oral halitosis: an update. Hong Kong Med J. 2004;10(6):414-418
11 - Gupta P, Gupta N, Pawar AP, Birajdar SS, Natt AS, Singh HP. Role of Sugar and Sugar Substitutes in Dental Caries: A Review. ISRN Dentistry. 2013;2013:1-5. doi:10.1155/2013/519421